探讨乙型肝炎疫苗不同接种剂量对不同孕龄早产儿免疫强或无(弱)应答的影响，抗体阳转率，抗－乙型肝炎表面抗体(HBsAb)滴度及免疫球蛋白(IgG，IgM和IgA)与补体(C3，C4)的变化。

选择2009年4月至2010年10月在本院新生儿科住院的270例早产儿及100例健康足月儿为研究对象。按照孕龄将其分为3组：孕龄<30孕周为90例(Ⅰ组)，30～33孕周为90例(Ⅱ组)，34～36孕周为90例(Ⅲ组)，≥37孕周的100例健康足月儿纳入对照组。每组婴儿再按照不同接种剂量(5 μg或10 μg)分为A，B亚组，免疫程序均为出生后第0，1，6个月接种(3针法)(本研究所遵循的程序符合本院人体试验委员会所制订的标准，并与患儿监护人签订临床研究知情同意书，分组征得患儿监护人的同意)。每组均于第3次接种乙型肝炎疫苗后4个月查抗－HBsAb滴度，IgG，IgM，IgA，C3及C4含量。若母亲是乙型肝炎病毒(HBV)携带者，所生新生儿出生12 h内注射乙型肝炎免疫球蛋白(HBIG)200 IU。比较各组乙型肝炎疫苗强或无(弱)应答率、抗体阳转率的差异，分析比较强应答与弱应答者免疫球蛋白水平变化。

各组受试婴儿未见明显局部与全身不良反应，均顺利完成临床试验。抗－HBsAb滴度在Ⅰ组A，Ⅱ组A，Ⅲ组A和对照组A间比较，差异无统计学意义(P>0.05)；抗－HBsAb滴度在Ⅰ组B，Ⅱ组B，Ⅲ组B和对照组B间比较，差异亦无统计学意义(P>0.05)。抗－HBsAb强应答所占百分比在Ⅰ组A，Ⅱ组A，Ⅲ组A和对照组A间比较，差异有统计学意义(P<0.05)；抗HBsAb强应答所占百分比在Ⅰ组B，Ⅱ组B，Ⅲ组B和对照组B间比较，差异亦有统计学意义(P<0.05)。免疫球蛋白(IgG，IgM，IgA)、补体(C3，C4)的变化：分别进行Ⅰ，Ⅱ，Ⅲ组A、B亚组与对照组比较，IgM，IgA，C3水平强应答早产儿明显高于无(弱)应答早产儿的水平(P<0.05)；B组乙型肝炎疫苗接种抗体阳转率明显高于A组(P<0. 05)；B组强应答早产儿IgG，IgM，IgA，C3及C4水平与A组强应答早产儿比较，差异无统计学意义(P>0.05)。

早产儿出生不久即接种乙型肝炎疫苗，未发现任何不良反应，其HBsAb水平产生较好，早产儿免疫强应答百分比低于足月儿，以孕龄<30孕周早产儿更为明显。高剂量乙型肝炎疫苗可提高早产儿乙型肝炎疫苗接种的免疫强应答百分比，强应答的早产儿比无(弱)应答早产儿有更好的体液免疫功能。

To investigate the strong or weak impact of immune response to different pregnant week premature infants in different dosage hepatitis B virus vaccine and the level changes of immune response rate, anti- hepatitis b surface(HBs) titer, Immunoglobulin (IgG, IgM, IgA) and complement (C)3, C4.

From April 2009 to October 2010, 270 case of premature and 100 cases of healthy full-term infants were recruited in the newborn department. Those cases were divided into 4 groups: <30 pregnant weeks (group Ⅰ, n=90), pregnant weeks from 30 to 33 weeks (group Ⅱ, n=90); pregnant weeks from 34 to 36 (group Ⅲ, n=90); pregnant weeks >37 weeks (control group, n=100). Then every group was sub-divided into group A(5 μg HB Vaccine) and group B (10 μg HB Vaccine) according to inoculation dose, the time of inoculation is at the 0, 1st and 6th month after birth. The anti-HBs titers, concentration of immunoglobulin (IgG, IgM, IgA) and complement (C3, C4) after four months from the third inoculation were examined. The newborns were injected 200 IU HBIG in 12 hours after the birth if his mother was hepatitis B virus carrier. Strong or weak response rates of hepatitis B vaccine in each group and the differences of seroconversion rate were compared. The changes of strong and weak response in immunoglobulin levels were analyzed.

No obvious local and systemic reaction was found in all groups and all tests were finished successfully. No significant differences of anti-HBs titer were found among group of Ⅰ-A, Ⅱ-A, Ⅲ-A and control group A (P>0.05), also among groupⅠ-B, Ⅱ-B, Ⅲ-B and control group B (P> 0.05). Statistically significant differences of anti-HBs strong response percentage were found amongⅠ-A, Ⅱ-A, Ⅲ-A and control group A (P<0.05); also among groupⅠ-B, Ⅱ-B, Ⅲ-B and control group B (P<0.05). Immunoglobulin (IgG, IgM, IgA) and complement (C3, C4) changes: Ⅰ, Ⅱ, Ⅲ and control groups were compared in A, and B groups, IgM, IgA, C3 strong response level significantly higher than no (weak) response level of premature infants (P<0.05); Group B of hepatitis B vaccine seroconversion rate was significantly higher than that of group A (P<0.05).

Premature infants with hepatitis B vaccine after birth did not find any adverse reaction, and the antibody levels generate better. Stronger response percentage of premature infants is lower than that of full-term infants, especially <30 pregnant-week premature infants. High-dose hepatitis B vaccine can improve the strong response percentage of premature hepatitis B vaccination. Premature infants with strong responses have better humoral immune function than infants without or weak response.